The control of expression of the Herpes Simplex virus (HSV) genome is being studied. Studies have emphasized the control of transcription of the HSV genome during productive infection. In particular two general areas are under investigation during this year: (1) Analysis of the size and sequence homology between polyadenylated HSV specific mRNA and its relation to mRNA methylation in general. BIBLIOGRAPHIC REFERENCES: Sutherland, B., Rice, M. and Wagner, E. Seroderma pigmentosum cells contain low photoreactivating enzyme levels. Proc. Natl. Acad. Sci. U.S. 72, 103-107 (1975). White, M., Wagner, E. and Tewari, K. Physio-chemical characterization of Novikoff Hepatome Mitochondrial DNA. Cancer Res. 35, 873-879 (1975).